Abstract
Individual food intake characteristics and indicators of gut physiology of group-housed weanling pigs were measured in relation to pre-weaning consumption of creep food. Additionally, the effects of creep food consumption on pre-weaning body weight and gain were assessed. A total of 48 litters was used in two trials. From 11 days of age until weaning (day 28), all 48 litters were given a creep food (12.7 MJ net energy (NE) per kg, 15.2 g lysine per kg) supplemented with 10 g chromium III oxide per kg. Piglets showing green-coloured faeces on three sampling days were designated as good eaters, whereas piglets that never showed green faeces were labelled as non-eaters. Piglets having green faeces once or twice were designated as moderate eaters. Based on availability, body weight, litter origin, genotype and gender 29 good eaters, 32 moderate eaters and 29 non-eaters were selected in the first trial. In the second trial there were 30 good eaters, 33 moderate eaters, and 27 non-eaters. In each trial eight piglets of each creep-food eating type were immediately killed to serve as a reference group. The remaining piglets of each eating type were weaned and placed in pens equipped with computerized feeding stations so that distributions of body weight, litter origin, and gender were similar within pens. In each trial, eight pigs of each eating type were killed 5 days after weaning in order to determine villous heights and crypt depths in the proximal small intestine and volatile fatty acid (VFA) concentrations in the colon. While being suckled, body weight was not related to the pre-weaning consumption of creep food (P > 0.1) whereas average daily gain of the good eaters during the creep feeding period was higher (P <0.05) than that of the moderate and non-eaters. Both morphology measures and VFA concentrations on the day of weaning were unaffected (P > 0.1) by the pre-weaning food consumption. After weaning, food intake and gain of the total group of good eaters were higher (P <0.05) than that of the non-eaters, whereas villous height and villous height : crypt depth ratios did not differ (P > 0.1). Neither total VFA concentration nor the proportion of branched-chain VFA were affected by creep food consumption while being suckled. Total VFA concentration in the colon was positively associated with body-weight gain (P <0.001). This study confirms earlier findings that consumption of creep food while being suckled stimulates food intake and growth after weaning. However, the beneficial effects were not associated with a prevention of damage to morphology of the small intestine.